GB886188A - Detergent compositions - Google Patents

Abstract

Solid detergent compositions comprise (a) an active detergent, e.g. soap, alkylbenzene sulphonate, fatty acyl isethionate, alkyl sulphate, or fatty acyl tauride, and (b) a perbenzoic acid which is substituted in the benzene nucleus with one or more nitro-, chloro-, cyano-, C1-4 alkyl or C1-4 alkoxy groups, and has a melting point not below 50 DEG C. Before incorporation into the composition, the per acid (b) is preferably mixed with such neutral or acid salts as sodium or ammonium sulphate, sodium bisulphate, or acid sodium pyrophosphate and then pelletted, the pellets so obtained being protected with a coat of inert material, e.g. paraffin wax having an iodine value not above 10 and a melting point not above 120 DEG F. The preferred per acids are the 2-, 3-, and 4- chloro-, the 2-, 3-, and 4- nitro-, the 3- and 4-methyl-, the 4-, methoxy-, the 4- tert. butyl-, the 4- isopropyl-, the 4- cyano-, and especially the 2:4- dichloroperbenzoic acids. The compositions may also include pyro- and tripolyphosphates, silicates, carboxymethylcellulose, fatty acyl alkanolamides, optical bleach, tarnish inhibitor, colour, and perfume. According to the Provisional Specifications the nuclear substituents of per acid (b) may include carboxyl-, bromo-and sulphonamidogroups and the benzene ring itself may form part of a fused system, as with a - and b - peroxynaphthoic acids.ALSO:Perbenzoic acid, which may be substituted in the benzene nucleus with one or more nitro-, chloro-, cyano-, C1-4 alkyl, or C1-4 alkoxy groups, is obtained by reacting the appropriately substituted dibenzoyl peroxide in chloroform with sodium methoxide in methanol in the absence of water at 0 DEG C. to-5 DEG C., adding icewater, separating and discarding the chloroform layer and the chloroform washings of the aqueous layer, acidifying with 10% sulphuric acid the residual aqueous layer, extracting the acidified aqueous layer with four separate portions of chloroform, drying the combined chloroform extracts over anhydrous sodium sulphate, and evaporating off the chloroform under reduced pressure. The acids obtained may be purified, (a) by recrystallization, by dissolving in the minimum amount of chloroform at room temperature followed by cooling to -40 DEG C., the mother liquor then being diluted with an equal volume of 40 DEG C.-60 DEG C. petroleum ether and cooled to -80 DEG C. to provide a second crop of crystals, or (b) by sublimation, when the acid is warmed to 40 DEG C.-50 DEG C. on a water bath and sublimed under vacuum on to a cold finger.ALSO:Bleaching compositions comprise (a) an active detergent, e.g soap, alkylbenzene sulphonate, alkyl sulphate or fatty acyl isethionate or tauride, and (b) a perbenzoic acid which is substituted in the nucleus with one or more chlorine atoms or nitro-, cyano, C1-4 alkyl or C1-4 alkoxy groups and has a melting point not below 50 DEG C. Before incorporation into the composition, the per acid (b) is preferably mixed with such neutral or acid salts as sodium or ammonium sulphate, sodium bisulphate, or acid sodium pyrophosphate and then pelletted, the pellets so obtained being protected with a coat of inert material, e.g. paraffin wax having an iodine value not above 10 and a melting point not above 120 DEG F. The preferred per acids are the 2-, 3-, and 4-chloro-; the 2-, 3-, and 4-nitro-; the 3-, and 4-methyl-; the 4-methoxy-; the 4-tert-butyl-; the 4-isopropyl-; the 4-cyano-; and especially the 2 : 4-dichloro-perbenzoic acids. The compositions, which may be used for bleaching cotton fabrics, may also include pyro- and tripoly-phosphates, silicates, carboxymethylcellulose, fatty acyl alkanol-amide, optical bleach, tarnish inhibitor, colour, and perfume. According to the Provisional Specification the nuclear substituents of per acid (b) may include bromine atoms or carboxyl- or sulphonamido-groups, and the benzene ring itself may form part of a fused system, as with a - and b -peroxynaphthoic acids.